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<h2>Limitations</h2>

When using ProGuard, you should be aware of a few technical issues, all of
which are easily avoided or resolved:
<p>
<ul class="spacious">

<li>For best results, ProGuard's optimization algorithms assume that the
    processed code never <b>intentionally throws NullPointerExceptions</b> or
    ArrayIndexOutOfBoundsExceptions, or even OutOfMemoryErrors or
    StackOverflowErrors, in order to achieve something useful. For instance,
    it may remove a method call <code>myObject.myMethod()</code> if that call
    wouldn't have any effect. It ignores the possibility that
    <code>myObject</code> might be null, causing a NullPointerException. In
    some way this is a good thing: optimized code may throw fewer exceptions.
    Should this entire assumption be false, you'll have to switch off
    optimization using the <code>-dontoptimize</code> option.</li>

<li>ProGuard's optimization algorithms currently also assume that the
    processed code never creates <b>busy-waiting loops</b> without at least
    testing on a volatile field. Again, it may remove such loops. Should this
    assumption be false, you'll have to switch off optimization using
    the <code>-dontoptimize</code> option.</li>

<li>When obfuscating, ProGuard writes out class files named
    "<code>a.class</code>", "<code>b.class</code>", etc. If a package contains
    a large number of classes, ProGuard may also write out
    <b>"<code>aux.class</code>"</b>. Inconveniently, Windows refuses to create
    files with this reserved name (among a few other names). It's generally
    better to write the output to a jar, in order to avoid such problems.</li>

</ul>

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<address>
Copyright &copy; 2002-2017
<a target="other" href="http://www.lafortune.eu/">Eric Lafortune</a> @ <a target="top" href="http://www.guardsquare.com/">GuardSquare</a>.
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